Railway car bearing seal spacer assembly

ABSTRACT

A bearing assembly is provided having a roller bearing with two cones defining an inner raceway fitted around the journal portion of an axle. A cup defines an outer raceway that combines with the inner raceway to receive roller elements. A spacer separates the cones, and a spacer support is provided to position and support the spacer.

BACKGROUND OF THE INVENTION

This invention relates to shaft journal bearings and, more particularly, to an improved bearing assembly spacer supporting arrangement for use in a railway freight car.

Roller bearing assemblies incorporating two rows of tapered roller bearings preassembled into a self-contained, pre-lubricated package for assembly onto journals at the ends of axles or shafts are known. Such bearing assemblies are used as rail car bearings assembled onto journals at the ends of the axles. Bearings of this type typically employ two rows of tapered roller bearings fitted one into each end of a common bearing cup with their respective bearing cones having an inner diameter dimensioned to provide an interference fit with the shaft journal and with a cylindrical sleeve or spacer positioned between the cones providing accurate spacing and proper lateral clearance on the journal. Seals mounted within each end of the bearing cup provide sealing contact with wear rings bearing against the outer ends or back face of the respective bearing cones at each end of the assembly. Such seals are shown in U.S. Pat. Nos. 5,975,533, 7,607,836, and 7,534,047.

In a typical rail car installation, the axle journal is machined with a fillet at the inboard end. A backing ring having a surface complementary to the contour of the fillet and an abutment surface for engaging the inboard end of an inner wear ring accurately position the bearing assembly on the journal. An end cap mounted on the end of the axle by bolts threaded into bores in the end of the axle engages the outboard wear ring and clamps the entire assembly on the end of the axle. The wear rings typically have an inner diameter dimensioned to provide interference fit with the journal over at least a portion of their length so that the entire assembly is pressed as a unit onto the end of the journal shaft portion of the axle.

It is desirable to assure the support and proper spacing of the cones by assuring the support and positioning of the spacer.

SUMMARY OF THE INVENTION

The bearing assembly of the present invention is a roller bearing that includes an inner race or cone fitted around the journal portion of the axle or shaft. The inner race formed by the cones includes an outwardly directed raceway. An outer race or cup has an inwardly directed raceway. Roller elements are located between and contacting the inner and outer raceways.

A backing ring has a contoured surface complementary to and engaging the contoured surface of a fillet formed on the shaft. The fillet leads from the journal to the shoulder of the shaft. The contoured surfaces cooperate to fix the backing ring against axial movement along the shaft.

The bearing assembly includes a seal assembly that provides a barrier for lubricant to be retained within the seal assembly and for contaminants to be kept out. A spacer is provided to assure the proper spacing of the two cones. A spacer support is provided to assure the proper positioning and support of the spacer during shipping and installation. The spacer support can remain in place after installation of the bearing assembly on an axle.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings,

FIG. 1 is a sectional view of a shaft journal having mounted thereon a tapered roller bearing assembly in accordance with an embodiment of the present invention;

FIG. 2 is an end view of a spacer support in accordance with an embodiment of the present invention, and

FIG. 3 is a detailed partial view in cross section of a tapered roller bearing spacer assembly in accordance with an embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to FIG. 1 of the drawings, a bearing assembly indicated generally by the reference numeral 10 on FIG. 1 is shown mounted on a journal 12 on the free, cantilevered end of a shaft or axle 14, typically a rail car axle. Journal 12 is machined to very close tolerances and terminates at its inner end in a contoured fillet 22 leading to a cylindrical shoulder 18 of axle 14. At the free end of the axle, journal portion 12 terminates in a slightly conical or tapered guide portion 24 dimensioned to facilitate installation of the bearing assembly onto the journal. A plurality of threaded bores 26 are formed in the end of axle 14 for receiving threaded cap screws, or bolts 28 for mounting a bearing retaining cap 30 on the end of the shaft to clamp the bearing in position as described more fully herein below.

Bearing assembly 10 is preassembled before being mounted and clamped on journal 12 by retaining cap 30 and bolts 28. The bearing assembly includes a unitary bearing cup or outer raceway 32 having a pair of inner facing raceways 34,36 formed one adjacent each end thereof which cooperate with a pair of bearing cones 38,40, having outer facing raceways respectively, to support the two rows of tapered rollers 42,44, respectively there between. A center spacer 46 is positioned between cones 38, 40 to maintain the cones in accurately spaced position relative to one another allowing for proper bearing lateral clearance.

Spacer support 72 is seen as a generally cylindrical unitary structure usually comprised of a plastic, such as a high density polyethylene. Spacer support 72 has a radially inner edge adjacent radially outward facing outer surface 73 of spacer 46. Spacer support 72 has a radially outer edge adjacent a radially inward facing center section 71 of cup 32. Spacer support 72 inner edge may engage or contact radially outward facing outer surface 73 of spacer 46.

Spacer support 72 outer edge 79 may engage or contact radially inward facing counter section 71 of cup 32. Whether or not actual contact is present, spacer support 72 acts to position and hold spacer 46 in position between cones 38 and 40 during shipping and assembly of bearing assembly 10. Spacer support 72 may initially upon installation for shipping contact both radially inward facing center section 71 of cup 32 and radially outward facing outer surface 73 of spacer 46, and after installation and wear in service, may contact one, both, or neither.

Bearing cup 32 is provided with cylindrical counterbores 17,19 at its axially outer ends and a pair first end sections 48, 50 of seal sections 52,54 are pressed one into each of the cylindrical counterbores 17,19 in cup 32. Each second end section 55, 63 of seal section 52,54 may include resilient sealing elements 56, 58 which rub upon and form a seal with radial outer surfaces 37,61 of a pair of seal wear rings 60,62 having an inwardly directed end in engagement with the outwardly directed ends of bearing cones 38,40 respectively. Seal section 54 is similar to seal section 52 and will not be described in detail. The other end of wear ring 60 is received in a cylindrical counterbore 64 in the axially outwardly directed end of an annular backing ring 66 which, in turn, has a counterbore 68 at its other end which is dimensioned to be received in interference and non-interference relation on the cylindrical shoulder 18 of shaft 14. The counterbore 64 and the outer diameter of wear ring 60 are also dimensioned to provide an interference fit so that wear ring 60 is pressed into the backing ring 66 which is accurately machined to provide a contoured inner surface 70 complementary to and engaging the contour of fillet 22 when the bearing is mounted on the shaft. The outwardly directed end of wear ring 62 bears against a counterbore 31 in a retaining cap 30.

Referring now to FIGS. 2 and 3, detailed views of spacer support 72 are provided, along with the positioning of spacer support 72 radially between cup 32 and spacer 46. Spacer support 72 has a radially inner edge that may include raised sections 77. Such raised sections 77 are adjacent and possibly would engage or contact radially outward facing outer surface 73 of spacer 46. Spacer support 72 has a radially facing outer edge 79 which is adjacent and possibly would engage or contact radially inward facing center section 71 of cup 32. 

1. A roller bearing assembly comprising: a generally cylindrical cone having a generally cylindrical, outwardly directed raceway thereon, a generally cylindrical cup having a generally cylindrical, inwardly directed raceway thereon, a generally cylindrical spacer adjacent the cone, the cone having a generally flat, axially inward face, the cup having a radially inward facing cylindrical counterbore, a generally cylindrical wear ring adjacent and axially inward from the generally flat, axially inward face of the cone, the wear ring having a generally cylindrical outer surface, a seal of generally cylindrical configuration, the seal having a first end section, an intermediate section and a second end section, the first end section received in the radially inward facing cylindrical counterbore of the cup, a resilient sealing element affixed to the second end section of the sealing element, the resilient sealing element contacting the generally cylindrical outer surface of the wear ring, and a spacer support of a generally cylindrical configuration having a radially inner edge adjacent the spacer and a radially outer edge adjacent the cup.
 2. The roller bearing assembly of claim 1 wherein the spacer support is comprised of a plastic.
 3. The roller bearing assembly of claim 1 wherein the spacer support is comprised of a high density polyethylene plastic.
 4. The roller bearing assembly of claim 1 wherein the radially inner edge of the spacer support includes a plurality of raised sections that extend toward the spacer.
 5. The roller bearing assembly of claim 1 wherein the cup includes a radially inward facing center section and the spacer includes a radially outward facing outer surface, and wherein the spacer support is between the radially inward facing center section of the cup and the radially outward facing surface of the spacer.
 6. The roller bearing assembly of claim 5 wherein the radially inner edge of the spacer support engages the radially outward facing outer surface of the spacer and the radially outer edge of the spacer support engages the radially inward facing center section of the cup.
 7. A roller bearing assembly comprising: a generally cylindrical cone having a generally cylindrical, outwardly directed raceway thereon, a generally cylindrical cup having a generally cylindrical, inwardly directed raceway thereon, a generally cylindrical spacer adjacent the cone, the cone having a generally flat, axially inward face, the cup having a radially inward facing cylindrical counterbore, a generally cylindrical wear ring adjacent and axially inward from the generally flat, axially inward face of the cone, the wear ring having a generally cylindrical outer surface, a seal of a generally cylindrical configuration, the seal having a first end section, an intermediate section and a second end section, the first end section received in the inward facing cylindrical counterbore of the cup, and a spacer support of a generally cylindrical configuration having a radially inner edge adjacent that spacer and a radially outer edge adjacent the cup.
 8. The roller bearing assembly of claim 7 wherein, the spacer support is comprised of a plastic.
 9. The roller bearing assembly of claim 7 wherein the spacer support is comprised of high density polyethylene plastic.
 10. The roller bearing assembly of claim 7 wherein the radially inner edge of the spacer support includes four plurality of raised sections that extend toward the spacer.
 11. The roller bearing assembly of claim 7 wherein the cup includes a radially inward facing center section and the spacer includes a radially outward facing outer surface, and wherein the spacer support is adjacent the radially inward facing center section of the cup and the radially outward facing surface of the spacer.
 12. The roller bearing assembly of claim 11 wherein the radially inner edge of the spacer support engages the radially outward facing outer surface of the spacer and the radially outer edge of the spacer support engages the radially inward facing center section of the cup. 